I did find for GROSSLANGENFELD on Wikipedia the following:
"Die erste urkundliche Erwähnung erfolgte 1283 als Langievield".
So the variant of the place name as Langenfeld was correct.
The german/diets/letzeburgs/dutch speaking area between Maastricht (NL) - Malmedy (BE) - Luxemburg (LUX) - Kronenburg/Scheleiden (D) did undergo turbulent changes between 1795 and 1839.
That region is the transition area between German, Dutch and French.
Grosslangenfeld did belong to the bishop of Trier. His territory has been divided between Belgium, Germany and the Grand-Duchy in 1795 and 1839.
For these reasons this posting will remain on this board. It will help others to solve some classic problems for this area.
But I suggest that a link, from the appropriate Rheinland board, with the correct title, should be made with this posting.
Thank you for communicating the result of your query.